Named as a formation of Bisbee Group for Still Ridge in sec 34, T24S, R21W, Hidalgo Co, NM within Pedregosa basin. No type section designated. Measured section in NW1/4 sec 34, T24S, R21W described. Geologic map included. Consists of very fine-grained, silty, arenaceous brown-weathering black conglomerate limestone and limestone conglomerate. The conglomerate is medium to thick-bedded, and forms small cliffs. Sandstone and limestone are prominent in the upper part. The sandstone is calcareous, light gray, thin to medium bedded, and cross-bedded. Sandy limestone is medium bedded, medium grained, gray and friable. Thickness is 575 to 658 ft. Conformably overlies Carbonate Hill limestone (new) and conformably overlain by Johnny Bull sandstone (new), both of Bisbee. Is of Early Cretaceous age. No fossils were found.

Source: GNU records (USGS DDS-6; Denver GNULEX).

Is top formation of Bisbee Group (Lower Cretaceous) in central Peloncillo Mountains, Hidalgo Co, NM in Pedregosa basin. Overlies Carbonate Hill Limestone (Aptian) of Gillerman (1958) of Bisbee. Underlies Johnny Bull Limestone (Upper Cretaceous) of Gillerman (1958). Is 685 ft thick. May be somewhat older than upper member (Albian) of Mural Limestone (Aptian to Albian) in Mule Mountains. [See fig. 5 for regional correlation.] Age is Aptian (Early Cretaceous) on basis of correlation.

Source: GNU records (USGS DDS-6; Denver GNULEX).

Is formation in Bisbee Group in central Peloncillo Mountains, Hidalgo Co, NM in Pedregosa basin. Mapped as single map unit with overlying Johnny Bull Sandstone. Is underlain by Carbonate Hill Limestone. Is intruded by units of Tertiary and Tertiary or Cretaceous age. Combined thickness of Still Ridge and Johnny Bull is 250-350 m. Is Early Cretaceous age on basis of stratigraphic position dating.

Source: GNU records (USGS DDS-6; Denver GNULEX).

Formation names of the Lower Cretaceous Bisbee Group used in Bisbee area (Glance Conglomerate, Morita Formation, Mural Limestone, and Cintura Formation) can be distinguished in Peloncillo Mountains (Cochise Co, AZ and Hidalgo Co, NM in Basin-and-Range province and in Pedregosa basin. Are recognized for the first time in northern Animas Mountains. Formation names of Bisbee area were defined by Ransome in 1904 and take precedence over local terminologies defined later (Gillerman, 1958, whose names McGhee Peak Formation, Johnny Bull Sandstone, Still Ridge Formation, and Carbonate Hill Limestone are not used in this report).

Source: GNU records (USGS DDS-6; Denver GNULEX).